Choke points

The following map highlights in color the stretches of major roads in the New York area that experience congestion.

A couple of improvements can be made:

The smaller roads should be left out completely rather than dimmed; as noted in the text box, congestion on smaller roads is ignored

More than two colors will bring out the difference between different roads better; as it stands, it is hard to see that 78 is the most congested. With more colors, the annotation would be rendered unnecessary